Photographic objective



' SR 7 I OR 3.043.191? q 0. LANGE ETAL PHOTOGRAPHIC OBJECTIVE FiledApril 25, 1961 July 10, 1962 SEARCH, RQOM United States Patent O3,043,193 PHOTOGRAPHIC OBJECTIVE Giinther Lange, Koenigsbronn,Wurttemberg, and Heinz Zajadatz, Aalen, Wurttemberg, Germany, assignorsto Carl Zeiss, Heidenheim (Brenz), Wurttemberg, German Filed Apr. 25,1961, Ser. No. 105,513 Claims priority, application Germany June 29,1960 1 Claim. (Cl. 88-57) The present invention concerns a photographicobjective consisting of two inner meniscus shaped dispersive compoundmembers including between them the diaphragm and turning their concavesides towards the diaphragm, and of two outer simple collective lenses.In

case a back focal length of about only 0.6-f and an image angle of aboutonly il8 is wanted, a good compromise between the aberrationsauthoritative for the image if the objective is so designed that thefollowing conditions are fulfilled in common:

In the following the design data are given for an ex- 7 emplaryembodiment of an objective according to the invention, for'which theaccompanying drawing FIGURE shows the lens section. In the FIGURE and inthe following table are designated With L; L the lenses,

r r the radii,

With d d, the axial distances, With n the refractive numbers, and With vthe Abbe-v-numbers.

The design data are normalized so that for the focal length thereresults the value f=1. The aperture ratio of this example amounts to1:2, the image angle to 218.

Patented July 10, 1962 Table surface Lenses Radll Axial 11d rdrefractive distances powers. 5 An/r n +0. 65859 +1. 04832 Ll d1 =0.07902 1. 69042 54. 80

38390 'dr=0. 00198 9 r 1. 297 Ln d;=0.13433 1. 61154 sass r4 =+l2. 493880. 00213 L111 d4=0. 03556 1. 58495 40. 65

dr=0. 29633 To 0. 30937 -2.18891 Lrv dr=0. 03951 1. 67718 32. 26 15 n2.38763 o.00555 Lv d1=0. 10668 1. 69042 54. 80

' da=0. 00198 rc +1. 88293 +0.36667 Lvx do=0. 13433 1. 69042 54. 80

no= 0. 89091 +0.77496 Back focal length r=0m4 Within the scope of thepresent invention are included especially those objectives the designdata of which approximate to close to the values to be taken from the 5foregoing table that none of the surface refractive powers (An/ r)deviates by more than 20.2-1/ f and none of the axial distances (d) bymore than $0.027 from the respective value given in the table.

We claim: Photographic objective consisting of two inner meniscus shapeddispersive compound members including between them the dia hragm turningtheir concave sides towards the diaphragm, and of two outer simplecollective lenses characterized by the combination of the followingfeatures:

(k) 1.00(r -r D 1.l(r r (l) 0.24-f r r r r r I --r r r r 3.0-f whereinare designated Withr r the radii of the individual surfaces, With (d +dthe thickness of the dispersive meniscus standing in front of thediaphragm,

With d, the diaphragm space,

and furthermore characterized in that its design values lie so close tothe data given in the following table that, none of the surfacerefractive powers (An/ r) differs abso lutely by more than 0.2-1/ f andnone of the axial dis- With (dg-i-dq) the thickness of the dispersivemeniscus

